A sensory yarn commonly has a thread core with a longitudinal central axis extending along the length of the yarn, referred to as the direction of extent. The thread core may be monofilic or made of several fibers or filaments. Preferably, the thread core is elastically extendible in the direction of extent. The extensibility of the sensory yarn may be adapted to the material in which the sensory yarn is integrated, and thus, may vary within a wide range.
In order to produce a capacitive component a first conductor and a second conductor are wound in a screw-like or helical form relative to the direction of extent. The sensory yarn may be configured as a twisted yarn or as a wrapped yarn. Consequently, the two conductors can be wound in and/or around the thread core. The two conductors are electrically insulated relative to each other. For example, at least one of the two conductors can be insulated by a varnish or a coating around the electrically conductive core.
For example, a sensory yarn has been described in DE 10 2008 003 122 A1. In that reference, the yarn is disposed for the detection of tensile stresses in a medical knit fabrics or knits. The yarn has a core thread around which—in one exemplary embodiment—a covering thread may be wound. If the yarn is curved or stretched in its direction of extent, the electrical property of the yarn changes, i.e., for example the electrical conductivity and/or capacitance. For example, the covering thread may be a bimetal thread.
DE 103 42 787 A1 describes an electrically conductive yarn, wherein at least one electrically conductive thread is wound around a core thread.
DE 10 2006 017 340 A1 discloses another electrically conductive yarn. A non-conductive multi-filament yarn that, preferably, is to deposit itself in a planar manner on the core thread is additionally wound around the electrically conductive thread that is wound around the core thread, so that, in the event of a contact of two electrically conductive yarns in a textile material, there will not form an inadvertent electrically conductive contact.
Presently, sensory textile materials are used in the diverse fields of applications. For example, such sensory textile materials are able to detect pushing forces, pulling forces or the like. In many applications, localization of the affecting force is advantageous or necessary. Frequently, the sensory yarns are incorporated in a dense matrix-shaped pattern of the textile material so that a two-dimensional pattern of intersecting sensory yarns is formed. If a force acts at a specific location on this surface or if an object approaches this surface, it is possible—depending on the density of the sensory yarn—to determine a location of the force or the approach of an object by means of the sensory matrix.
The costs of manufacture for such sensory textile materials are great, as a result of which the textile material becomes accordingly expense. As a result of this, the use of sensory textile materials continues to be minimal.